Banning all NON-ASCII chars in nicknames

Hey, i want to get rid of people with special chars in their names on my server. For example "TestUser ♥".

I tried some regex'es i found on google like:

http://ift.tt/1LyS2C7
http://ift.tt/1LyS1Om
http://ift.tt/1LyS2Sp

The method that should work seems like:

Code:

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.*[^\x00-\x7F].*

---

but it does not filter anything.

Banning all NON-ASCII chars in nicknames